Electric control for carrier system



C. W. MCKEE ETAL ELECTRIC CONTROLI FOR CARRIER SYSTEM May'14, 1963 2 Sheets-Shui. 1

Filed Jan. 8, 1960 QQ L/ J L/ May 14, 1963 c. w. MCKEE ETAL ELECTRIC CONTROL FCR CARRIER SYSTEM 2 Sheets-Sheet 2 Filed Jan. 8, 1960 United States Patent O 3,689,432 ELECTRIC CONTROL FOR CARRIER SYSTEM Chester W. McKee and Harry D. McKee, Flossnioor, Ill., assignors to Welding Service, Inc., Franklin Park, Ill., a corporation of California Filed Jim. s, 1960, ser. No. 1,356 3 Claims. (Cl. 104-88) Generally, previously available remote control devices for carrier systems lhave included a switch or photocell located at each station of operation and positioned so as to be selectively actuated by a corresponding lever or light source, as the case may be, disposed on the carrier. Such remote control devices have been relatively expensive -and complicated since extensive interconnecting wiring is required, and complicated remote initial adjustment must be made.

An object of the present invention is the provision of an improved control device for a carrier system. Another object of the present invention is the provision of a control device for selectively routing carriers in a carrier systern. A further object is the provision of a control device for a conveyor system which selectively controls the branch conveyor to which the carrier is consigned. Still a further object is the provision of a comp-act control device for a carrier system which is relatively inexpensive and simple to manufacture.

Other objects and advantages of the present invention will become apparent by reference to the following description and `accompanying drawing.

In the drawing:

FIGURE 1 is a schematic diagram of a control device showing various features of the present invention, the control device being applied to an overhead conveyor system;

FIGURE 2 is :a Vertical cross section of the control device; and

FIGURE '3 is a cross sectional view taken generally along line 3 3 of FIGURE 2.

A control device in accordance with the present invention is designed to be used in combination with a carrier system which includes at least one carrier moving along a path of travel. A plurality of station-s are located along the path, and mean-s are provided at each station for performing an operation. The control device comprises a strip of magnetizable material, `and means for magnetizing a selected area of the strip when the carrier is at a predetermined location along the path. A switch, which is actuated by the magnetized area, is disposed along the strip and is connected so as to actuate the operationpertorming means. Means are provided for moving the strip relative to the switch at a speed which is correlated with the speed of the carrier along the path of travel.

To facilitate the understanding of the invention, a brief description of the operation of the carrier system is set forth hereinafter. 'Ihe carrier system shown in the draw ings is a conventional overhead-monoral system, adapted to be used in a slaughtering plant. The sides of meat are loaded on carriers or trolleys 10, one side to a trolley, at a room where the :animals are killed and dressed. The loaded trolleys 10 lare then stored in sequence on a plurality of storage rails (not shown) until the meat is graded.

When the grading operation begins, each trolley 10 is propelled along a main conveyor track 12 by a main conveyor drive chain 14 past a grading station 16. At the 3,0%,432 Patented May 14, 1953 lCe grading station 16, an operator determines the grade of the meat and aotuates a consignment switch 18 on a control device 20 to select a branch conveyor 22 Where similar grades of meats are to be stored.

When the trolley 10 is adjacent a siding switch 24 leading into the selected branch conveyor 22, `the control device 20 causes the siding switch 24 to be switched. The trolley It) is then propelled by the main conveyor 14 onto the siding switch 24 :and thence onto a branch conveyor track 26. As the trolley 10 is moved onto the branch conveyor track 26, the trolley 10 is engaged by a branch conveyor drive chain 28, which is started by the control device 20. When the trolley 10 is clear of the siding switch 24, the siding switch 24 is switched back to its normal position and the branch conveyor drive chain 28 is stopped.

To remove a selected grade of meat from the branch conveyor 22, the operator actuates a push button or shipping switch 30 associated with the branch conveyor 22 where the selected grade of meat is stored. The -actuation of the push button 3d switches an exit track switch 32 associated with the selected branch conveyor 22 and energizes the branch conveyor drive chain 2.8. The branch conveyor drive chain 28 propels the trolley 10 onto the exit switch 32 and thence onto an exit or shipping track 34 Where an exit .or shipping drive chain 36 engages the trolley 16. The exit track switch 32 is maintained in its switched position until the trolley 10 is clear of the switch 32, at which time the switch 32 is moved back to its normal position and the branch conveyor drive chain 28 is stopped.

More particularly, the trolleys Ill are propelled along the main conveyor track l2 by a spaced apart pusher arms 3S carried by the main conveyor drive chain le. The branch or storage conveyors 22 are disposed at right angles to the main conveyor track 12. Each branch conveyor 22 includes the track 26 connected at one end to the main conveyor track l2 by the siding switch 2d which is operated by a solenoid 4t). yA plurality of spaced apart pusher arms 42, which are carried by the branch conveyor chain 28, are disposed so as to engage the trolleys lltl as the trolleys are propelled onto the branch conveyor track 26, The chain 23 is driven by a motor 44 suitably connected thereto.

rEhe other ends of the branch conveyor tracks 26 are connected to the shipping or exit conveyor track 34 by the exit switch 32 which is operated by a solenoid 46. A plurality of spaced apart pusher arms 4S are carried by the exit conveyor drive chain 36, the pusher arms 43 being adapted to engage the trolleys 1l) as they are propelled onto the exit conveyor track 24.

As shown in FIGURES 2 and 3, the control device 2d includes a plurality of strips or rings 50 of a suitable magnetizable material, such as magnetizable iron, disposed in spaced apart relationship on a drum 52 of a nonmagnetizable material, such as aluminum. One ring 5o is associated with each branch conveyor 22. The drum 52 is ixedly attached to a shaft 54 which is journalled in bearings 56 disposed in the side walls 58 of a housing 6l).

The shaft 54 and the drum 52 are rotated by a synchro motor 62, the speed of the motor 62 being controlled by a synchro generator 64 connected to the main conveyor drive chain llt. In this way, the peripheral speed of the rings 5d is in direct proportion to the speed of the trolley le. The circumference of the rings 5d is made such that before the rings 5t)` make one complete revolution, one of the trolleys 1l) can be propelled from the grading station le to a position past the branch conveyor 22 last in line.

Since the periphery of the rings Sll is moving at a speed which is in direct proportion to the speed of the trolley lt?, fthe distance between two points on the periphery of the o rings Sil is proportional to the distance travelled by the trolley l0. Accordingly, the siding switch 2d may be operated at the proper time to shunt the trolley lll onto the selected branch conveyor track 26 by magnetizing a selected area of the ring 5t? associated with the branch conveyor a2, when the trolley itl is at a predetermined location on the main conveyor track, and employing the magnetized area to operate a magnetic operated switch positioned along the rings 50.

ln the illustrated embodiment, a selected area of the ring Sti is maguetized by an electromaguet 63, suitably supported by the housing di) so as to be adjacent the periphery of the ring Sil. The electromagnet 63 is actuated by manually closing the consignment switch 18, the switch 18 being connected in series with the electromagnet 65 and a power source which, for purposes of illnstration, is shown as a battery 7i).

So that the electromagnet 68 is actuated when the trolley lil is at a predetermined location on the main conveyor track l2, a main control switch 72 is provided which is actuated by the trolley i@ as it moves along the main conveyor track l2. The main control switch 72 is connected in series with the power source 7G and the parallel connected consignment switches itl.

The solenoid lo of the associated siding switch 2d is actuated just before the trolley it? reaches the associated siding switch 24 by the magnetized area of the ring 50 actuating the magnetic operated switch 65 which is suitably supported by the housing adjacent the periphery of the ring 5G. The operating arm of the illustrated magnetic operated switch 66 is provided with a roller 74 of a soft magnetic material which is attracted by the magnetized area on the ring 5G. The magnetic operated switch 66 is disposed at a distance from the electromagnet 68 which is in the same proportion to the distance from the main control switch 72 to siding switch 2d as the speed of the ring Stl is to the speed of the trolley lil.

The magnetic operated switch 66 is connected in series with the power source '76 and a pilot relay 76. For purposes of clarity, a portion of the conductor extending between the switch 66 and the power source 7o is not shown in the drawing. The two ends of the conductor are each indicated by an arrow designated by X "his scheme is followed hereinafter for connections between the power source and the parts of the circuit. lt should be understood that all Xs are connected together. When the pilot relay 76 is energized by the closing of the magnetic operated switch 66, a normally open contact 7S, which is operated by the relay 76, is closed. The Contact 78 is connected in series with the siding switch solenoid de and the power source 7o, and thus the siding switch 24 is transferred by the closing of the contact 7S.

Since the siding switch 2d should be maintained in a transferred condition until the trolley lltl has` been propelled onto the branch conveyor track 26, a holding circuit is provided for the siding switch solenoid r`he holding circuit includes a holding relay 8@ which is connected in parallel with the siding switch solenoid A normally open contact S2 of the holding relay is connected in series with a normally closed Contact @d of a timing relay S6, and the series combination is connected in parallel with the pilot relay contact 78 to thereby by-pass the contact '73.

As the trolley 10 is propelled into the branch conveyor 22, it is received by the pusher arms 42 carried by the branch conveyor chain 2S. The drive motor 44 of the branch conveyor chain 28 is energized by the closing of a normally open contact 8S of the holding relay Si), the contact 88 being connected between the power source 70 and the drive motor 44.

As the trolley lll is propelled along the branch conveyor track 26, it closes a normally open timing switch 9G which is connected in series with the power source '70 and the timing relay 86. The timing relay 86 becomes energized and opens the normally closed contact 84 thereof. Accordingly, the current is interrupted to the siding 4 switch solenoid 4t) and the drive motor 44 of the branch conveyor 22, and thus the branch conveyor chain 28 is stopped and the siding switch 24 is returned to its normal position by a spring (not shown).

The magnetized area of the ring S8 is erased by a permanent magnet 91 which is suitably supported by the housing 60 adjacent the periphery of the ring St) immediately before the electromaguet 68. It should be understood that more than one magnetized area may appear on the ring 50 and it is not necessary to wait for the magnetized area to be erased before maguetizing a second area of the ring 50. In addition, more than one ring Sti may be magnetized during one revolution of the ring Sil.

.The sorting process may be continued until the branch conveyor track 26 are filled with trolleys lll, or may be stopped at any time prior to this.

When it is desired to remove trolleys .10 from the branch conveyors 22, the shipping conveyor drive chain 36 is started. Then, the normally open shipping switch Si?, which is associated with the selected branch conveyor 22 from which the trolley 1t) is to be removed, is closed. As shown in the drawings, the closing of the shipping switch 30 completes a circuit from the power source to the solenoid 46 which, upon energization, op erates the exit switch 32. The shipping switch 30 also energizes an auxiliary relay 92 which is connected in parallel with the exit switch solenoid 46. A normally open contact 94 of the auxiliary relay 92 is connected in series with a normally closed contact 96 of an output relay 98, and the series combination is connected in parallel with the shipping switch 30. In this way, the solenoid d6 is kept energized until one of the trolleys 10 is propelled from therbranch conveyor track 26 onto the shipping conveyor track 34.

A normally open contact 100 of the auxiliary relay 92 is connected in parallel with the normally open contact SS of the holding relay so that the branch conveyor drive motor 44 is energized when the shipping switch 30 is closed. Accordingly, when the shipping switch 39 is closed, the branch conveyor 22 propels the trolley 10` out of the branch conveyor 22 onto the shipping conveyor track 34.

As the trolley 10 is propelled onto the shipping conveyor track 34, it operates an output switch 162. When the output switch 102 closes, it energizes the output relay 98, which isv connected in series therewith. The energization of the output relay 9S causes its associated normally closed contact 96 to open, thereby deenergizing the exit switch solenoid 46 and the brauch line conveyor drive motor 44.

in operation, the loaded trolley is propelled past an operator who determines to which brauch conveyor 22 the trolley l@ is to be consigned. The operator closes the consignment switch 18 associated with the selected branch conveyor 22 and, when the main control switch 'i2 is closed by the trolley lil, a selected area of the ring Sil, which is associated with the selected branch conveyor 22, is magnetized. The trolley 10 is propelled along the main conveyor track 12 until it reaches a position just before the selected branch conveyor 22. The Yrnagnetized area on the associated ring Sti then actuates the magnetic operated switch 66 which, in turn, actuates the pilot relay '76. The closing of the normally open Contact 78 of the pilot relay 76 energizes the solenoid 49, which operates the siding switch 24, and a holding relay The energization of the holding relay 8i) and the closing of its contacts 82 and S3 causes the branch conveyor drive motor 44 to be activated and keeps the solenoid 4@ energized until the trolley '10 actuates the timing switch 9G. The closing of the timing switch 90 energizes the timing relay 36, and the contact 34 of the timing relay 86, in turn, deenergizes the solenoid 40 and apaga-s2 the branch conveyor drive motor 44. Consequently, the siding switch 24 returns to its normal position.

-lt should be apparent from the above that a control device constructed in accordance with the invention provides a compact, readily adjustable, and easily operated control for a conveyor system. Moreover, it should be understood that the control device may be used with conveyors other than the conveyor illustrated in the drawing. For example, the control device may be used to stop a conveyor as the carrier reaches certain remote stations. Also, the control device may be employed to control the operation of equipment, such as paint sprayers, driers, etc.

Various modiiications may be made in the above described control device, without deviating from the spirit or scope of this invention. Various features of the invention are set forth in the accompanying claims.

We claim:

l. A control device `for a carrier systemincluding a plurality of carriers moving along a path of travel, a plurality of stations located along the path, and means at each station for performing an ioperaiton, said control device comprising a plurality of coextensive, mechanically interconnected endless strips of magnetizable material, one of said strips being provided for each station, means associated with each strip for perpendicularly magnetizing a selected area of the outer surface of its strip; means for selectively energizing said magnetizing means when one of the carriers is at a predetermined location on said path, a switch associated with each endless strip for actuating the operation-performing means of the station vfor which sai-d .strip is provided, each switch including an operating arm, :and a roller of magnetic material on said a-rm, said roller being `disposed adjacent the outer surface of its strip so as to be attracted by the magnetic field of said selected area to thereby move said arm and aotuate said switch, means for moving said strips relative to said switches and to said energizing means at a speed which is in the same proportion to the speed of the carrier along the path of travel as the distance from the magnetizing means on one strip to the roller on the same strip is t0 the distance from said predetermined location to a location on said path immediately before the station for which said .strip is provided, and means disposed along each endless strip after said magnetic operated switch for erasing the magnetized area.

2 A control device 'for a carrier system including a plurality of carriers moving along a path of travel, a plurality of stations located along the path, and means at each station for performing an operation, said control device comprising a plurality of rotatably mounted, coaxial rings of magnetizable material, one of said rings being provided for each station, means associated with each ring `for perpendicularly magnetizing a selected area of its ring, means for selectively energizing said magnetizing means when one of the carriers is at a predetermined location on said path, la switch associated with each ring for actuating the openation-perorming means of the station for which its ring is provided, each switch including an operating arm, and a roller of magnetic material connected to said arm so that movement of the roller effects operation of said switch, said roller being disposed along and adjacent the periphery of its ring so as to be moved by the magnetic lield of the selected area, means for rotating said rings relative to said switches and said energizing means at -a speed which is in the same proportion to the speed of the carrier along the path of travel as the distance from the magnetizing means on one ring to the roller on the same ring is to the distance from said predetermined location to a location on said path immediately before the station for which said ring is provided, and means disposed along each ring after said switch lfor erasing the magnetized area.

3. A control device for a carrier system including a plurality of carriers moving along a path of travel, a plurality of stations located along the path, means at each station for perlforming an operation, said control device comprising a rotatably mounted drumhaving a plurality of rings o-f magnetizable material thereon, one of said rings being provided for each station, an electromagnet associated with each ring and disposed adjacent said ring for perpendiculatly magnetizing a selected area o its ring, a power source, a switch actuated by said carrier when said carrier is at a predetermined location on the path, a selector switch associated with each ring connected in series with said power source and said electromagnet for selectively energizing said electromagnet, a switch associated with each `ring for actuating the operation performing means for which its ring is provided, said switch being disposed along the periphery of said ring and having an operating arm, and a roller of magnetic material carried by said arm and disposed adjacent the periphery of its ring, means for rotating Said drum at a speed which is in lthe same proportion to the speed of the carrier along the path of travel as the distance from the electromagnet to the magnetic roller is to the distance from said predetermined location t-o a -location on said path immediately before the associated station, and means disposed along said ring after said magnetic operated switch for erasing the magnetized area.

References Cited in the tile of this patent UNITED STATES PATENTS 2,497,874 Evans Feb. 2l, 1950 2,590,091 Devol Mar. 25, 1952 2,614,169 Cohen Oct. 14, 1952 2,714,355 Benson Aug. 2, 1955 2,770,796 Boer Nov. 13, 1956 2,825,476 Muller Mar. 4, 1958 2,835,206 Gordon May 20, 1958 2,909,128 Keen Oct. 20, 1959 2,912,678 Robinson et al. Nov. l0, 1959 2,941,666 Sims .Tune 2l, 1960 FOREIGN PATENTS 609,731 Germany Mar. 8, 1935 

1. A CONTROL DEVICE FOR A CARRIER SYSTEM INCLUDING A PLURALITY OF CARRIERS MOVING ALONG A PATH OF TRAVEL, A PLURALITY OF STATIONS LOCATED ALONG THE PATH, AND MEANS AT EACH STATION FOR PERFORMING AN OPERATION, SAID CONTROL DEVICE COMPRISING A PLURALITY OF COEXTENSIVE, MECHANICALLY INTERCONNECTED ENDLESS STRIPS OF MAGNETIZABLE MATERIAL, ONE OF SAID STRIPS BEING PROVIDED FOR EACH STATION, MEANS ASSOCIATED WITH EACH STRIP FOR PERPENDICULARLY MAGNETIZING A SELECTED AREA OF THE OUTER SURFACE OF ITS STRIPS; MEANS FOR SELECTIVELY ENERGIZING SAID MAGNETIZING MEANS WHEN ONE OF THE CARRIERS IS AT A PREDETERMINED LOCATION ON SAID PATH, A SWITCH ASSOCIATED WITH EACH ENDLESS STRIP FOR ACTUATING THE OPERATION-PERFORMING MEANS OF THE STATION FOR WHICH SAID STRIP IS PROVIDED, EACH SWITCH INCLUDING AN OPERATING ARM, AND A ROLLER OF MAGNETIC MATERIAL ON SAID ARM, SAID ROLLER BEING DISPOSED ADJACENT THE OUTER SURFACE OF ITS STRIP SO AS TO BE ATTRACTED BY THE MAGNETIC FIELD OF SAID SELECTED AREA TO THEREBY MOVE SAID ARM AND ACTUATE SAID SWITCH, MEANS FOR MOVING SAID STRIPS RELATIVE TO SAID SWITCHES AND TO SAID ENERGIZING MEANS AT A SPEED WHICH IS IN THE SAME PROPORTION TO THE SPEED OF THE CARRIER ALONG THE PATH OF TRAVEL AS THE DISTANCE FROM THE MAGNETIZING MEANS ON ONE STRIP TO THE ROLLER ON THE SAME STRIP IS TO THE DISTANCE FROM SAID PREDETERMINED LOCATION TO A LOCATION ON SAID PATH IMMEDIATELY BEFORE THE STATION FOR WHICH SAID STRIP IS PROVIDED, AND MEANS DISPOSED ALONG EACH ENDLESS STRIP AFTER SAID MAGNETIC OPERATED SWITCH FOR ERASING THE MAGNETIZED AREA. 